Vitamin B12 Hydrophobic Derivative Exhibits Bioactivity: Biomedical and Photophysical Study

Vitamin B 12 (cyanocobalamin) and some of its hydrophilic derivatives are used as antidotes and also to treat megaloblastic anemia, nerve myelination disorders, and liver pathology. This work presents results of a comparative experimental study of cyanocobalamin and its derivatives aquacobalamin and heptamethyl ester of cyanoaquacobyrinic acid. In a model of thiosemicarbazide seizures in rats, aquacobalamin contributed to a lengthening of the seizure latency period while cyanocobalamin contributed to a decrease in the seizure latency period and to a decrease in seizures. Histological study of the brain samples showed that all investigated compounds exhibited an antispasmodic effect as well as neuroprotective and myelinating effects. For the first time it was shown that a derivative of vitamin B 12 , which has hydrophobic substituents—heptamethyl ester of cyanoaquacobyrinic acid, also exhibits biological activity and, therefore, is of interest for further research. Analysis of changes in the electronic absorption spectra recorded during the interaction of aquacobalamin with thiosemicarbazide indicated possibility of direct interaction of thiosemicarbazide with aquacobalamin.